Russia says it invaded Ukraine to halt Kyiv's ambitions to join NATO, the U.S.-led defensive alliance, which it saw as a major security threat. It also accuses Kyiv of persecuting ethnic Russians and their culture in Ukraine.

The Russian leader senses a chance for more international recognition, while his American counterpart hopes to play peacemaker.

When U.S. President Donald Trump and Russian President Vladimir Putin met in Helsinki in 2018, the pair alarmed allies with a friendly encounter where Trump sided with the Russian leader over his own intelligence agencies on election interference.